Telephone receiver



June 8 1926.

S. GERNSBACK TELEPHONE RECEIVER Filed May 12, 1928 Patented June 8, 1926,

LSSZSS SIDNEY GERNSBACK, OF NEW YORK, 1\T. Y.

TELEPHONE RECETLVER.

Application led May 12, 1923.

This invention relates to telephone receivers.r and more jiarticularly to an `adjustable receiver lor radio phones.

An object of the invention is to provide a receiver in which 'the distance between the pole piece and the diaphragm may-be adjusted. l

A further object is the provision of adjusting means t'or moderate priced receivers.

ln the accompanying` drawings, l have shown one embodiment of the invention. In this showing:

Figure 1 is a perspective view oit the receiver,

Figure 2 is ay Central vertical sectional view showing the pole piece arranged rela.- tively close to the diaphragm,

Figure 3 is a siinilar view showing the pole piece adjusted at a distance trein the diaphragm, and,

Figure el; is a transverse sectional view on line L.bwl ot' Figure 2.

Referring` to the drawings, the reference numeral l designates a suitable casing ot the usual construction formed of suitable.

insulating' material. The casing` may be termed oi any desired insulating` material.

but l have found that a casing or shell termed ot turned wood not only possesses the necessary insulating` qualities but, in addition, has very good acoustic qualities. The casing is provided with a. cover 2, having' an interiorly threaded flange 3, adapted to engage external threads on the top olf the rasing. The cover is pro vided with a. eentral openi el.

diaphr .ein is arranged in the casing in the nsnal'mininer and is adapted to be vibrateffl by the magnet. i inagi'iet G is arranged in the casing` and is provided with a pole piece 7 supported on. a screw S. rillicscrew passes through an opening??- in the bottom oit the casing;- substantially centrally thereof and received in a threaded openl in 9 in the pole piece. A rubber gasket l0 is arranged between the casing.;v and 'the magnet. In place ol" a rubber gasket, a gasket of any other compressible material, such as felt or other tibrous material, may be employed or a metallic. spring may be employed. Suitable lead wires 1l are connested to the magnet in the usual manner.

in the use of the receiver, the pole piece may be adjusted toward and awa-y from the diaphragm by turning the screw in the Serial No. 638,645.

opening 9. Withthe parts in the position shown in Figure 2 Yot the drawings, the screw is partially removed from the openingr -9 and the pole piece is arranged relatively close to the diaphragm. The gasket l0 is then expanded. To withdraw the pole piece trein the diaphragm, the screw. is turned into the opening 9, drawing the pole piece toward the. base oft the casing' and placing; the gasket under compression, as shown .in Figure -3 ot the drawings.

l'leretoiore adjustable receivers had been more or less expensive and by means ot the present invention, I provide an adjustable receiver in which the only additional parts employed are a machine screw and a rubber gasket. further advantage o'l this receiver is the elimination ot' labor in assembling` it. In the ordinary receiver` skilled labor is necessary in assembling. The pole piece must be adjusted to be the same height as the rim ol: the telephone casing and this distance .must be gauged very accurately, frequently relpiiringr the pole piece or the rim ol the casing` to be `ground oli'. This necessity of accurate adjustment in assertibling, is eliminated by' means ot the present invention as the pole piece may be adjusted at any time by ineans et the screw 8.

it is to be understood that the to'm ot my intention herewith shown and described is to be taken as a preferred example oil' the saine. and that various changes in the shape, size, and arrangement et parts may be resorted to without departing from the spirit et the inveinion or the scope oit the subjoined claim.

Haring' thus described my invention, I claim Ain adjustable telephone receiver comprising a casing' 'formed ot turned wood, a cover n'ionnted on said casing, a diaphragn'i arranged in said casing adjacent said cover,

.a .I 'nagijnet arranfcred centrally in said casing' adjacent said diaphragm, a pole piece ar-- ran ad in said magnet, a disc arranged agg inst said pole piece, a single compressi-- ble gasket arranged between said disc and said casing coaxial with said pole piece, said. pole piece being' provided with an axial -threaded opening, and a screw extending' through said casing and said gasket and received in said opening.

In testimony whereof, I afliX my signature.

SIDNEY GERNSIBACK. 

